Submission #213567

#	Time	Username	Problem	Language	Result	Execution time	Memory
213567		usachevd0	Nautilus (BOI19_nautilus)	C++14	100 / 100	286 ms	896 KiB

nautilus

#include <bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define all(a) (a).begin(), (a).end()

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef long double ld;

template<typename T1, typename T2> bool chkmin(T1 &x, T2 y) { return y < x ? (x = y, true) : false; }
template<typename T1, typename T2> bool chkmax(T1 &x, T2 y) { return y > x ? (x = y, true) : false; }

void debug_out()
{
    cerr << endl;
}

template<typename T1, typename... T2> void debug_out(T1 A, T2... B)
{
    cerr << ' ' << A;
    debug_out(B...);
}

#ifdef DEBUG
    #define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
    #define debug(...) 42
#endif

const int maxN = 502;
int n, m, k;
using BitSet = bitset<maxN * maxN>;
BitSet dp[2];
BitSet grid;
BitSet E, W;

signed main()
{
#ifdef DEBUG
    freopen("in", "r", stdin);
#endif
    ios::sync_with_stdio(0);
    cin.tie(0);

    cin >> n >> m >> k;
    for (int i = 0; i < n; ++i)
    {
        string s;
        cin >> s;
        for (int j = 0; j < m; ++j)
        {
            if (s[j] == '.')
            {
                grid[i * m + j] = 1;
            }
        }
    }
    E = grid;
    for (int i = 0; i < n; ++i)
        E[i * m] = 0;
    W = grid;
    for (int i = 0; i < n; ++i)
        W[i * m + m - 1] = 0;
    dp[0] = grid;
    
    string I;
    cin >> I;
    for (int l = 1; l <= k; ++l)
    {
        dp[l & 1].reset();
        char c = I[l - 1];
        if (c == 'E' || c == '?')
        {
            dp[l & 1] |= E & (dp[l & 1 ^ 1] << 1);
        }
        if (c == 'W' || c == '?')
        {
            dp[l & 1] |= W & (dp[l & 1 ^ 1] >> 1);
        }
        if (c == 'S' || c == '?')
        {
            dp[l & 1] |= grid & (dp[l & 1 ^ 1] << m);
        }
        if (c == 'N' || c == '?')
        {
            dp[l & 1] |= grid & (dp[l & 1 ^ 1] >> m);
        }
    }
    cout << dp[k & 1].count() << '\n';

    return 0;
}

Compilation message (stderr)

nautilus.cpp: In function 'int main()':
nautilus.cpp:81:36: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
             dp[l & 1] |= E & (dp[l & 1 ^ 1] << 1);
                                  ~~^~~
nautilus.cpp:85:36: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
             dp[l & 1] |= W & (dp[l & 1 ^ 1] >> 1);
                                  ~~^~~
nautilus.cpp:89:39: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
             dp[l & 1] |= grid & (dp[l & 1 ^ 1] << m);
                                     ~~^~~
nautilus.cpp:93:39: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
             dp[l & 1] |= grid & (dp[l & 1 ^ 1] >> m);
                                     ~~^~~

• Subtask 1: 29 / 29
• Subtask 2: 37 / 37
• Subtask 3: 34 / 34